Element Stories - Protactinium

Protactinium is an element with atomic number 91, belonging to the actinide series in the periodic table, and is a radioactive metal. It is known as a silvery-gray metal, and all of its isotopes are radioactive. In nature, isotopes like protactinium-234 are present in trace amounts, generated during the decay of uranium-238. The most stable isotope, protactinium-231, has a half-life of approximately 32,700 years. Protactinium-231 is an intermediate product in the decay chain of uranium-235, ultimately leading to stable lead-207. Due to its rarity and strong radioactivity, protactinium has almost no common industrial applications and is primarily used in research on radioactive decay and nuclear physics. Additionally, analyzing the ratio of protactinium to thorium in marine sediments can aid in studying past marine environments and sedimentation processes. In space, it can be formed through processes like stellar nucleosynthesis and supernovae, but it tends to decay into other radioactive elements rather than remaining for long periods.